I think you’re focusing on mass market stuff too much and you’re tech-brained. Publishers are basically necessary for non fiction as you need fact checkers, legal cover if making claims about humans that might sue you and research access and assistance.

Marketing help is needed for anything that isn’t already popular, income is needed while you work, editing is an extremely hard job that is a profession for a reason. Relying on something like patreon or YouTube where you have no real rights is an extremely precarious way to live open only to people with extremely specific skills around self promotion.

There are reasons beyond authors being dumbshits why Australian authors struggle and every author ever will tell you it’s a terrible way to make bread.